Three weeks ago, while looking for something else, I came across one of the most extraordinary documents I have ever read. It relates to an organisation called Arise (Associates for Research into the Science of Enjoyment). Though largely forgotten today, in the 1990s it was one of the world's most influential public-health groups. First I should explain what it claimed to stand for.

Arise, founded in 1988, seems to have been active until 2004. It described itself as "a worldwide association of eminent scientists who act as independent commentators". Its purpose, these eminent scientists said, was to show how "everyday pleasures, such as eating chocolate, smoking, drinking tea, coffee and alcohol, contribute to the quality of life".

It maintained that there were good reasons for dropping our inhibitions and indulging ourselves. "Scientific studies show that enjoying the simple pleasures in life, without feeling guilty, can reduce stress and increase resistance to disease ... Conversely, guilt can increase stress and undermine the immune system ... This can lead to, for instance, forgetfulness, eating disorders, heart problems or brain damage." The "health police", as Arise sometimes called them, could be causing more harm than good.

Arise received an astonishing amount of coverage. Between September 1993 and March 1994, for example, it generated 195 newspaper articles and radio and television interviews, in places such as the Wall Street Journal, the International Herald Tribune, the Independent, the Evening Standard, El País, La Repubblica, Rai and the BBC. Much of this coverage resulted from a Mori poll, called Naughty but Nice, that Arise claimed to have commissioned, into the guilty pleasures people enjoyed most. Here is a typical example (this one from Reuters):

"Puritanical health workers who dictate whether people should smoke or drink alcohol and coffee are trying to ruin the quality of life, a group of academics said ... 'Many of us hold the view that it is a person's right to enjoy these pleasures ...' said Professor David Warburton, a professor of pharmacology at Reading University in England ... 'Much of health promotion is based on misinformation. It is politically driven'."

The Today programme gave Warburton an uncontested interview in its prime spot - at 8.20am. He extolled the calming properties of cigarettes and poured scorn on public-health messages. Arise has also featured eight times in the Guardian. Coverage like this continued until October 2004, when the Times repeated Arise's claim that we should stop "worrying about often ill-founded health scares" and "listen to our bodies, which naturally seek to protect themselves from disease by doing the things we enjoy." In hundreds of articles and transcripts covering its claims, I have found just one instance of a journalist - Madeleine Bunting in the Guardian - questioning either Arise's science or the motivation of the scientists.

Warburton, who claimed to run the group, was head of psychopharmacology at the University of Reading. While Arise was active he published at least a dozen articles on nicotine in the academic press. In 1989, in the Psychologist, he mocked the US surgeon general's finding that nicotine is addictive. Most of his articles were published in the journal Psychopharmacology, of which he was a senior editor. They maintained that nicotine improved both attention and memory. I have read seven of these papers. On none of them could I find a declaration of financial interests, except for two grants from the Wellcome Trust.

In 1998, as part of a settlement of a class action against the tobacco companies in the US, the firms were obliged to place their internal documents in a public archive. Among them is the one I came across last month. It is a memo from an executive in the corporate services department of Philip Morris - the world's largest tobacco company - to one of her colleagues. The title is "Arise 1994-95 Activities and Funding". "I had a meeting," she began, "with Charles Hay and Jacqui Smithson (Rothmans) to agree on the 1994-1995 activity plan for Arise and to discuss the funding needed. Enclosed is a copy of our presentation."

This showed that in the previous financial year Arise had received $373,400: $2,000 from Coca-Cola, $900 from other firms and the rest - over 99% - from Philip Morris, British American Tobacco, RJ Reynolds and Rothmans. In 1994-95 its budget would be $773,750. Rothmans and RJ Reynolds had each committed to provide $200,000, and BAT "has also shown interest". She suggested that Philip Morris put up $300,000. Then the memo becomes even more interesting.

"The previous 'Naughty but Nice' Mori poll proved to be very effective in getting wide media coverage. The exercise will be repeated this year on the theme of 'Stress in the Workplace' ... A draft questionnaire was already submitted to [Tony Andrade, Philip Morris's senior lawyer] and [Matt Winokur, its director of regulatory affairs] for comments." "We decided to hold" Arise's next conference in Europe, it continued, because of "positive European media coverage". Philip Morris had appointed a London PR agency to run the media operation, set up Arise's secretariat and help to recruit new members. Arise's "major spending authorisation and approval would be handled by an 'informal' Budget Committee involving PM, Rothmans and possibly RJR and BAT".

The memo suggests Arise was run not by eminent scientists but by eminent tobacco companies. This impression is reinforced by another document in the tobacco archive, which explains how the group began. "In 1988 the US Surgeon General said: 'Nicotine was as addictive as heroin or cocaine.' The industry responded. A group of academics was identified and called together to: - review the science of substance abuse, - separate nicotine from these substances".

I sent a list of questions to Warburton, but he told me that he did not have time to answer them. Reading University replied that it knew Warburton's work had been sponsored by the tobacco companies. Indeed, the university itself had received over £300,000 from Arise, but "from the university's standpoint, the source of funding for Arise has always been vague". It revealed that "Professor Warburton and the University of Reading were in receipt of BAT research funding between 1995 and 2003". But at no time had it questioned this funding or sought to oblige Warburton to declare his interests in academic papers. Astonishingly, it suggested that this would amount to "censorship" and "restricting academic freedom".

The journal Psychopharmacology told me it was unaware Warburton had been taking money from tobacco firms. "It is an author's responsibility to disclose sources of funding, and widely understood that journals themselves do not expect to police this declaration." After a long career untroubled by questions about his interests or professional ethics, Warburton retired in 2003. He still lectures at Reading as an emeritus professor.

How much more science is being published in academic journals with undeclared interests like these? How many more media campaigns against "overregulation", the "compensation culture" or "unfounded public fears" have been secretly funded and steered by corporations? How many more undeclared recipients of corporate money have been appearing on the Today programme, providing free public relations for their sponsors? This case suggests that academia and the media have failed dismally to exercise sufficient scepticism. Surely there is one obvious question with which every journal and every journalist should begin. "Who's funding you?"